User`s guide

3-50
Configuring
describe a few configurations and possible solutions that address
this problem.
Scenario 1: Local Stations
Problem:
Assume station A has already communicated and the ATX has
learned it as a local transparent station. If station A has a MTU of
anything greater than 4500 and wants to transfer a file to station B,
it will not work.
Reason:
The ATX has no way of telling station A that it can not handle
frames greater than 4500 because it is not passing traffic to station
A with the Routing Control field. Station A will be able to connect
to station B. However, if a file transfer is requested by A it will try
to transfer that file at the largest frame size that A and B have
negotiated. Assuming that B is configured the same as A, this file
transfer will not happen because the maximum frame size on
FDDI is 4500.
Solution:
The end station has to be configured for a MTU of less than the
maximum frame size of the transport media (i.e., FDDI, Ethernet
or Fast Ethernet).
A
ATX WITH
FDDI
B
SRTB
ENABLED
ATX WITH
SRTB
ENABLED
SR ONLY
BRIDGE
C
SR ONLY
BRIDGE
D